Back Firing Trough the exhaust.

[Guest]

Hi everyone! I have a 60 Tbird (sunroof) and I love it, but today driving back from a car show I was getting a lot of back firing. The car idles fine, starts right away and seems to have power but sometime shutters and then back fires through the exhaust. My fear is that it's a worn out timing chain/spocket, but I was wondering if it could be something else. The car has a 1964 390 engine in it. The only thing I did to the car right before driving to the show was to put in some lead substitute. Maybe I put in too much?? I am just looking for any possible ideas to look into first before I have to do the timing chain repair. Is it possible to have carb problems.

Any thoughts from you TBIRD lovers?

Thanks- Jack

[Guest]

RE: Back Firing Trough the exhaust.

Maybe you should check your PCV system......or the heat riser on your exhaust. Also check the carb .........you may be running too rich.

[Guest]

RE: Back Firing Trough the exhaust.

rotor button, crack in dis.cap.

[Guest]

RE: Back Firing Trough the exhaust.

YIKES !!! My father always tells me when I go off the deepend.......Its probably something simple and stupid.

[JohnG]

RE: Back Firing Trough the exhaust.

After I bought mine, I found that the ignition timing would change more than 5 degrees after I set it (or thought I set it). I finally found that the bushing in the distributor were worn out and the shaft could move around changing the geometry of the points and thus the timing. This is easily checked by taking the rotor off and grabbing the shaft to see if there is side to side play.

Probably not your problem but worth checking anyway. I was able to buy a new distributor over the counter at the local auto parts store for about $50 or so, so its not a financial disaster if yours if shot.

IF yours is good, check for an oil port on the side (little flap you open up and put oil in) on the distributor. If you have one, get some oil in there while the bushings are still good. I suspect this did not get done in many cases leading to worn out distributors.

I later found the timing chain was worn as well - the two items probably age together.

John
58 Hardtop

[Guest]

RE: Back Firing Trough the exhaust.

Hey Thanks!

All good things to check. I just notice oil on spark plugs 1 & 3. Not good. Change plugs, the car back fired a bit, then was steady. I drove in about 5-6 miles with hard accerelation and then back off. Didn't notice and back firing. So, now at least, I know it's not the timing chain. However, it looks like I have engine problems with oil leaking in the cylinders I guess. I am going to still check on some of the other things people metioned. Especailly the PCV. I agree, it could be something simple, that why I ask for everyones experience. Maybe it won't be a simple fix, but at least I'll know I didn't waste my money. If I have to rebuild the engine I think I'll go for a Re-manufactured one. (not rebuilt) Especially a 352 if I can get it.

Any experiences with re-mans??? Good, bad, etc. I like to know in case I have to bite the big bucks. (I starting to get ready to slap on the knee pads with my darling wife, if it needs a new engine.) I just can't see doing a small rebuild and then paying more money afterwards.

Thanks again everyone!

Jack

[Guest]

RE: Back Firing Trough the exhaust.

If its not burning oil.........then the problem is your valve seals. I run my 58 (original engine) with a product called CD-2 lead additive. .........but......you can have your heads rebuilt, new seals and hardened valves so you can run unleaded gas. If your seals are worn or cracked......oil from the top of the heads can run down into your pistons after the car is turned off.

[byersmtrco]

RE: Back Firing Trough the exhaust.

If it still has breaker points, change those too (or update to electronic ign) But points will certainly make it pop thru the exh, as will fouling plugs. if that's the case, I'm sure it's your valve guides.

As far as reman engines, I have one coming from S & S eng in Washington. I've dealt with this company before with older GM engines and a regular on this board (Mr 390 Edelbrock) has one in his 60. I should have it installed in a month or so. The price was right ($1700 aprox incl core & shpg) But, it comes with a 7/70 warr. It will be 9.5-1 compr with a mild (RV) cam. So it oughta pull pretty good and run on Calif pump gas. I'll keep you all up to date on that.

[Guest]

RE: Back Firing Trough the exhaust.

Hi!

Your right! I don't see any smoke come out of the tail pipes at all. I started to use CD2 butI only had the car for 7 mos. You talked about new seals/harden valves etc. I believe (with my limited knowledge ) that exactly the problem, even though the car seems to be running OK now since I changed the plugs and added bit of oil sealer additive.

So the question is, how much does a repair like this usually cost. (ball park) I am assuming they don't have to pull the engine out to do this, correct? The rest of the engine seems fine, and if this buys me 3-4 years that's great, if the cost is $300 -$600. I have a local mechanic that charges around $75/hr.

Let me know, and thanks for your answer. Actually, I thank everyone for there help!! It's good to have this support and good for others to read these pages for trouble shooting.

Jack

[Guest]

RE: Back Firing Trough the exhaust.

Yes, I'll be real interested in how you engine turned out. I might go the cheaper route to fix my problem if it is under $600 dollars. I also found an engine for $1,600 but came with only a 3 yr 36K warranty, I forget the place but that included shipping the engine & the core back. I believe the warranty was transferable also. (always a good option.)

Are you doing the replacement yourself?? If not, what are you expecting the labor and other matl cost to run? $1000-1500? I was telling my wife that it might cost about $2,700 total but wasn't sure.

Thanks- Jack

[Guest]

RE: Back Firing Trough the exhaust.

If your seals are leaky......you will get the usual "smoke at startup" then it disapears................You can have your heads "revamped" and slapped back on......but Im not sure of the cost.